In the process of replacing roof coverings on gable roof building with roofs made of asphalt shingles or the like, the shingles are commonly allowed to slide down the roof onto the lawn, grass, shrubbery, and other plants, resulting in an unsightly appearance, damage to the plants and sometimes permanents damage to the grass and shrubbery, particularly in hot weather when the ambient heat burns the plants. Moreover, it is a time consuming laborious job in cleaning up the pieces of shingles, scraps of wood and the like.